What do you do when you kill someone?

"Cry," he said, half-kidding.

This is not a question you get to ask every day. My passenger is not a serial killer (at least, not a deliberate one). Instead, he drives freight trains for a living. And in the course of his job, he has inadvertently killed someone.

Another driver he knows has killed three people. Apparently it happens all the time. Homeless people wander on the tracks and pass out. Suicides lie down on the tracks. "I saw the guy I killed, saw him clear as day. He had laid down with his head on one of the rails. I blew the whistle and he never even moved. We dragged him almost half a mile before we could stop."

This is something a lot of the people who get killed inadvertently do not realize: Trains require a long, long, long distance to stop. Even if they are moving slowly—and oftentimes they only look like they're moving slowly—they weigh a hell of a lot, and that much inertia means a very slow stop.

I ask if he had bad dreams about the man he killed. "A friend of mine was hit by someone running a red light at high speed. His cab was thrown up onto the curb, where it hit and killed a homeless man. He had nightmares for weeks."

This man was luckier; he has made his peace with what happened. Hopefully the man he accidentally killed is also finally at peace.